Granted Patent
Utility
US 6,133,475 · App. 09/091,289
Process for producing 2-hydroxynaphthalene-3,6-dicarboxylic acid
Inventors:
Ryuzo Ueno, Masaya Kitayama, Yoshiro Uchiyama, Syungo Nara
Patented Case
View Patent ↗
Granted: Oct 17, 2000
Filed: Jun 16, 1998
Inventors
Ryuzo Ueno
Masaya Kitayama
Yoshiro Uchiyama
Syungo Nara
Assignee (at issue)
Kabushiki Kaisha Ueno Seiyaku Oyo Kenkyujo
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.